Summary
Autoimmunity involves the constant activation and reactivation of new B cells, meaning that new pathogenic antibodies can be created at any point (1). The severity of the disease correlates with the proportion of active antibodies circulating in blood.
See also
1.
Robinson WH. Sequencing the functional antibody repertoire—diagnostic and therapeutic discovery. Nature Reviews Rheumatology. 2014;11(3):171–82. Available from: https://doi.org/10.1038/nrrheum.2014.220